pg_fetch_all和pg_fetch_assoc效率

Question

Is pg_fetch_all function more efficient than the snippet

while( $res = pg_fetch_assoc($rs) ) 
{
    $out[] = $res;
}

I am wondering how pg_fetch_all is internally implemented. I want to know whether the while- approach is (much) less efficient than using this function and why.

Answer 1

Internally both snippets include cycles looping through all the fetched rows, so they are quite similar in terms of efficiency. internal implementation of pg_fetch_all